Winch with cable tension device



Dec. 9, 1958 M H, E, PAPE 2,863,636

WINCH WITH CABLE TENSION DEVICE Filed Feb. 25, 1955 n 4 Sheets-Sheet llfm/71 lDec. 9, 1958 M. H. E. PAPE 2,863,636

l WINCH WITH CABLE TENSION DEVICE Filed Feb'. 23, 1955 4 'sheets-sheet 2Dec.. 9, 1958 Filed Feb. 23, 1955 1yr. H. E. PAPE 2,863,636

WINCH WITH CABLE TENSION DEVICE 4 Sheets-Sheet 3 Dec. 9, 1958 M. H. E.PAPE 2,863,636

WINCH WITH CABLE TENSION DEVICE Filed Feb. 25, 1955 4 Sheets-Sheet 4WINCH WITH CABLE TENSION DEVICE Martin Herrmann Emil Pape, deceased,late of Hamburg, Germany; Margarete M. J. Stolleis, heir of two-thirdsand Edda M. E. Stolleis, heir of one-third ot' the estate of said Pape,assignors to Willi Baensch, Hamburg- Altona, Germany, a hrm ApplicationFebruary 23, 1955, Serial No. 490,105

Claims priority, application Germany February 23, 1954 3 Claims. (Cl.254-172) The invention relates to hydraulically controlled Wincheswhich, without appreciable ralteration of their normal construction, canby an additional device solve the problem of automatically unwinding orwinding up a cable while maintaining a given cable tension. Such aproblem is posed when a vessel is moored to the lock walls in a lock, asare present for example between the North American lakes, and a desiredcable force must be maintained, if the water level and Vessel rapidlyfall or rise, Without necessitating attention. The same need arises inthe rapid loading of a vessel from bunkers, in the rise and fall of avessel o-n the tide, and in dumping the cargo of a vessel, which shouldlie or be held at a certain distance from the roadstead in front of theanchor.

Such warping Winches (known as mooring Winches abroad) were previouslymade as separate Winches and constructed essentially as steam Winches.

The invention provides a dual function for hydraulically regulatedWinches in that the Winches can be used as loading winches in theirnormal construction and also as mooring Winches, whereby in the latercase a desired and even adjustable cable tension is automaticallymaintained in both directions (rising and falling).

The type of hydraulic winch with which the invention may be used is ofthe known construction which cornprises a pump or primary part, drivenfrom a power source, supplying pressurized fluid to an hydraulic motoror secondary part which in turn rotates the Winch drum. Control meansare used to regulate the output of the pump whereby the hydraulic motorand drum may be selectively rotated in either direction at infinitelyvariable speeds and torques.

Basically, an object of the invention is to automatically maintain agiven tension in the rope or cable being wound or unWound on the Winchdrum by comparing the pressure of the fluid being supplied tothehydraulic motor by the pump to a preselected force produced by a springto maintain a given tension on the rope. This may be achieved by the useof a piston, acted upon by the output iiuid of the pump, compressing aspring of knowncharacteristics whereby a rise in fluid pressure willfurther compress the spring and a decrease in pressure will cause thevpiston to move under the inuence of the spring. The movement of thepiston may be coupled by a mechanical connection to the control meansregulating the pump output whereby an increase or decrease of the fluidpressure from the predetermined spring value will automatically vresultin a compensating movement of the pump control rising of the vesselcorresponding to the Winding up of the nited States APatent O 2,863,636Patented Dec. 9, 1958 ice cable moored to the bank, it will beunderstood that, if

Vachieved between the hydraulic pressure and the spring force, wherebythe cable velocity and the velocity of rise of the vessel are in theproper relation. An inequality of these two quantities involves eitherloosening of the cable, hence reduction of the driving liquid pressure,whereby the pump supplies a greater amount of liquid, i. e., greatercable winding velocity or additional tension of the cable with theopposite effect (increase of the liquid pressure, enhanced springcompression, decrease of liquid amount, i. e. smaller cable velocity).

In the reverse lock operation, i. e. on lowering of the vessel, thespring must have the tendency to alter the output of the pump to aminimum, hence also the liquid quantity to a minimum, which is oppositeto raising of the vessel for in lowering of the Vessel, the cable mustbe unwound. Excessive unwinding would make the cable slack, decreasingthe hydraulic pressure, so that the excessive spring force must decreasethe liquid quantity and hence the lowering velocity. That is also does,and the pump forced into its lowering position beyond the neutralposition does directly what is required of it. Unfortunately themechanical etiiciency, and also the hydraulic` eiciency, is reversed andassumes very different size values as in winding of the cable. Rising ofthe vessel is comparable with the winding up of a load, while unwindingcompares to the lowering of the load. If now in the first case theetliciency is o7, it is, as is well konwn, in the second case 21;-1. Inthe case of the hydraulically adjusted loading winch, the amount i. e.in unwinding the cable (lowering) with a given cable force,theoretically only half the liquid pressure within the hydraulic motoris necessary as in cable winding (rising) with the same cable force. Asit is desired to use the same spring, piston and connecting meansbetween the piston and pump controls for both winding and unwindingoperations, it will be apparent that the reduced pressure required tomaintain a given cable tension during unwinding of the drum, in respectto the Winding or raising operation, necessitates means to cornpensatefor this phenomenon and such compensating structure is provided by theinvention. This effect is obtained according to the invention asfollows: Two pistons are provided which move in common axial movement bya disc to which they areV both secured. During the winding operationonly .one piston is subject to liquid pressure as described below. Atthe moment where the two pistons are in a position where the pump outputis zero the two pistons communicate with the pressure liquid so that thedouble piston surface is available from this instant, so that aconsiderably decreased pressure, as arises only by the backwardetliciency of 21;-1 brings the regulating device into operation despitedecreased hydraulic pressure and multiplied spring forces. According tothe size of n and the ratio the diameter of the second piston maydeviate from the diameter of rst piston to operate to the satisfactionof said ratios. As given in the later description of the example, supplyand withdrawal of the pressure liquid for the second piston iscontrolled by the piston itself.

The automatic longitudinal movement of the pistons is transmitted by arack coupled to it from the hand control wheel regulating theY pumpoutput. The biasing `tenson of the spring can be altered by a settingscrew whereby it is possible to set the spring forces and hence thecable forces to a higher or lower level.

If the loading winch is to be used as a mooring winch, all that isnecessary for such a change is turning a small hand crank through 90. Bythis (1) a linked rack is engaged, (2) the hydraulic supply valvebetween the drive and pistons is opened and (3) the hand control wheelis brought into the greatest setting, rising, since only thus can thesmall hand crank be turned into the in position.

A preferred example of the construction is described below:

Fig. l represents a graph illustrating various characteristics of theinvention,

Fig. 2 shows a longitudinal section through the parts essential for theinvention,

Fig. 3 shows a transverse section substantially along the line III- IIIof Fig. 2,

Fig. 4 shows a horizontal section through the two control cylinders,

Fig. 5 shows a section along the line V-V of Fig. 4,

Fig. 6 shows a section through the control cylinders similar to those ofFig. 4, wherein the two control cylinders are in the neutral position (Oposition of Fig. l), and

Fig. 7 shows a section like Fig. 6, but with the pistons in the lefthand end position corresponding to position I of Fig. l.

Figs. 8 and 9 illustrate general schematic elevational and end views ofa possible arrangement of the components of the winch, the pump, motorand base forming no part of the invention.

The winch is provided with a liquid drive operating upon thedisplacement principle which includes a pump or primary part driving amotor or secondary part which rotates the winch drum. For reversing itsoperation the pump output is adjustable in either direction from aneutral position, whereas the motor part can be influenced automaticallyin either direction of rotation as abo-ve mentioned. An example of aliquid drive employing the above principles is shown in Patent No.2,186,409 disclosing a typical general construction wherein a variableoutput pump is employed to drive a hydraulic motor at varying speeds andtorques.

According to Figs. 2 to 6, in the vicinity of the hand lever 1 fromwhich a pump output control drum 2 is operated, a housing 3 is providedconsisting of several parts. The control drum 2 is operatively connectedto the pump to adjust the pump output, both directional andquantitywise, and consequently the motor characteristics of thehydraulic drive. In one direction of rotation of the hand lever 1,winding of the winch drum and cable is caused and in the other directionunwinding of the drum results. 4 indicates a part of the outer housingof the liquid drive. A possible arrangement of the components of a winchemploying such structure is generally shown in Figs. 8 and 9, whereinthe winch structure is supported upon a base 48 and includes a powersource 41, drivingly connected to the liquid drive 42 which in turnrotates the winch drum 50, as desired.

A spring 5 is arranged in the housing 3 and contacts at one end a springplate 6 and at the other end spring disc 7 which is backed by a rollerbearing S on a nut 39 which is screwed into one part of the housing 3. Acover 40 encloses the hole and serves Vsimultaneously as a lock nut forthe nut 39. By screwing the nut 39 in or out, the tension of the spring5 can be altered.

Two pistons 9, 10 arranged side by side are secured in any way to thespring plate 6 and are movably arranged in the housing 3. Two operatingspaces 11, 12 are created in this way which are enclosed by covers 13,14.

A bolt or plunger 15 is also secured to the plate 6 in a manner notshown in detail which takes part in the inward and outward movements ofthe pistons 9, 10 as further described below. The bolt or plunger 15 islikewise guided in the housing 3 and rigidly connected with a rack 16,which engages with a toothed segment 17 rigidly connected with a shaft18 which is rotatably mounted in a projection 19 upon the housing 3.

The cylinder space 11 of the piston 9 is connected at the connection 20for iluid communication with the pressure or output side (of the pump orprimary part) of the hydraulic drive. Both pistons 9, 10 are shown inFig. 4 in the end position in which the pump operates with the maximumdesired driving amount and the most rapid rising or winding up takesplace. Thus, only the piston 9 is subjected to the fluid pressuresupplied from the pump to the hydraulic motor when the pistons 9 and 10are in the position shown in Fig. 4. As the fluid pressure rises, as inthe case when the resistance to rotation of the winch drum increasesresulting from increased tension in the rope or cable, the piston 9 willbe forced toward the left compressing spring 5 and should the pressuredecrease the spring 5 will move the piston 9 to the right, as viewed inFig. 4.

When the pistons are moved to the 'position shown in Fig. 6, which isthe neutral position, the uid within cylinder 11 may now communicatewith cylinder 12 by means of the intersecting annular grooves 21 and 22formed in cylinders 11 and 12, respectively. Thus, once pistons 9 and 10are in the position of Fig. 6 both pistons are subjected to the pumpoutput pressure in all positions to the left and greater forces areexerted on spring 5 due to the greater piston area subjected to thefluid pressure. The function and operation of this construction will belater described.

The piston 10 is provided with a central drilling 23 fro-m the base ofwhich extend preferably a number of radial drillings 24. During thefirst part of the movement of the piston 10, the operating space 12 ofthis piston communicates by way of the central drilling 23 and thedrilling 24 with an annular space 25 which is connected to the dischargeby a connection 26. As soon as the piston 9 frees the annular space 21an-d the operating space 12 has become connected with the pressuremedium supply, the connection of the drillings 24 with the annular space25 is interrupted, whereby the operating space 12 is shut oit from thedischarge.

The discharge of the pressure medium from the operating space 12 withthe piston returning to its initial position can then occur againthrough the drilling 23, the radial drillings 24 and the annular space25. In Fig. 6, the position of the two pistons 9, 10 is shown in theinstant where the operating space 12 has been connected with thepressure medium supply and shut off from the pressure medium discharge.In Fig. 7 the Iposition of the two pistons 9, 10 shown is the left-handend position, which thus corresponds with the maximum unwindingposition.

A lever 27 is keyed to the shaft 13 and a rack 28 is connected to it,the teeth of which mesh with the teeth of a gear wheel 29, which isrigidly connected with hand lever 1. Therefore, a mechanical connectionis made between the piston movements and the means controlling the pumpoutput which permits the device to operate as follows:

As stated above, the object of the invention is to provide automaticmeans for maintaining a given cable or rope tension on a hydraulic winchand such control is achieved by maintaining a balance between the forceexerted by spring 5 and the force produced by the Huid pressure actingonpistons 9 and 10. Thus, initially the nut 39 is rotated to produce apredetermined compression of m assai-:6:31a

spring 5, the lever 1 is then rotated to rotate drum 2 and regulate thepump output to either wind or unwind the drum as desired. For instance,where it is desired to maintain a given tension in a cable aflixed to avessel which is rising, as in a lock or incoming tide, the lever 1 isrotated to cause'the winch drum to Wind up and due to the connectionbetween gear Wheel Z9 and spring plate 6 via rack 28, lever 27, rack andpinion 16 and 17, and plunger 1S the pistons 9 and 1@ will be moved tothe position shown in Fig. 4 where only piston 9 is subject to the uidpressure of the pump output. Once lever 1 is in the wind position theWinch drum will rapidly rotate to take up the cable slack, the pressurewithin cylinder space 11 will be small at this time. When the cablebecomes taut the pressure within cylinder 11 will rise and upon thefluid pressure reaching a value suflicient to overcome the presettension in spring 5 the piston 9 will begin to move to the left, Fig. 4.Such movement will cause plunger 15, rack 16, rack 28 to move, rotatinggear wheel 29 in a direction to reduce the pump output, thus decreasingthe cable tension and uid pressure within cylinder 11, as the pumpoutput is decreased a point is reached where the spring force is greaterthan the fluid force and spring 5 will then move the piston 9 and plate6 to the right within a resulting rotation of gear wheel 29whichincreases the output of the pump to a point where a balance ismaintained between the force exerted by spring 5 and that produced bythe iluid pressure. This pressure is that necessary to produce thedesired tension in the cable or rope al'lxed to the vessel. Therefore,it will be understood that the pump output pressure will beautomatically regulated to produce a given tension in the cable at alltimes irrespective of how fast or slow the vessel rises. To increase thecable tension the nut 39 must be rotated to further compress spring 5necessitating a higher Huid pressure to initiate movement of piston 9 orconversely a lower tension may be maintained by decreasing thecompression of spring 5 resulting in a lower pressure being supplied bythe pump.

To maintain the proper tension in a vessel lowering on a tide or in alock, the lever 1 is ro-tatcd in the opposite direction to that toproduce winding of the cable. Such rotation of lever 1 will positionpistons 9 and 10 as shown in Fig. 7 wherein the pressurized pump fluidhas access to both cylinders l1 and 12 increasing the eiective area ofthe uid acting on spring S. The increase in area is necessary fortworeasons, the iirst being that less fluid pressure is required tomaintain a given cable tension during unwinding as compared withwinding, as explained above, secondly, as the spring 5 is compressed toa greatci extent during the unwinding operation more force must beexerted by the iluid than in the winding phase.

During unwinding the operation is similar to winding except the pressurerelationship is reversed. Initially, the lever 1 is rotated to maximumunwind, however, if tne cable becomes slack the pump output pressurewill decrease and pistons 9 and 10 will be moved to the right by spring5 decreasing the pump output quantity slowing the unwinding of the drumto a point where a balance is achieved between spring and iiuidpressure. If the cable unwinds too slowly the Huid pressure withincylinders 11 and 12 will move plate 6 to the left compressing the spring5 with a resultant rotation of wheel 29 to increase pump output andcause faster unwinding.

By proper relationship of the spring properties to the pistons 9 andIii, which are preferably or substantially equal size, the same initialsetting of the spring 5 to produce a particular cable tension duringwinding or unwinding may be obtained.

The theory of operation is graphically illustrated in Fig. l wherein thevertical coordinates I', O and I represent maximum unwinding pumpoutput, neutral or zero pump output and maximum winding pump output,respectively. The lines S represent cable or rope tension, F is thespring force, Q is uid quantity, V cable velocity and a is the fluidpressure lat the pump output or discharge. As will be noted, the fluidpressure at the pump outlet a is less during unwinding than winding fora given cable tension yet the spring forces are greater. Thus, thenecessity for increased piston area during the unwinding operation.

To insure that the rack 23 is properly oriented to the gear wheel 29each time the rack and gear are engaged, a hand lever 30 is providedwhich is rotatably mounted at 31 in a rigid part. This hand lever isconnected by a rod 32 with a pin 33 which engages in a longitudinalgroove 34 in the rack 28. The hand lever 30 also includes a pin 35 whichcan enter an arcuate groove 37 by way of a radial groove 36 in the gearwheel 29. The radial groove 36 is so arranged that the pin 35 can onlyenter it when the hand lever 1 has set the pump by way of the controldrum 2 to its greatest output capacity during rising or winding up. Therod 32 is arranged at the same time so that, when the pin 35 enters thearcuate groove 37, the rack 28 is in engagement with the gear wheel 29and hence the pump output can be adjusted in dependency upon theposition of the pistons 9, 10 and hence upon the supply pressure of thepump part.

The hand lever Sii also acts upon a shut-01T device 38 which is insertedin the duct which leads to the pressure medium connection 20. In thepositio-n of the lever 30 shown (Fig. 2) this shut-off device 38 isopened, the pistons 9, 10 thus being under the influence of the supplypressure of the pump part for automatic winch control.

When the lever 3i) is turned through 90 into the out position shown bydot-dash lines (this is only possible if the gear wheel 29 is in theposition of Fig. 2), the shutoff device 33 is simultaneously closed. Thedevice described is thus disconnected which serves for the use of thewinch as a loading winch. The winch can be used as a mooring winch againby operating lever 30 to open device 38 and engage rack 28.

What is claimed is:

l. In a hydraulic winch employing a cable drum and having a primary orpump part drivingly communicating with a secondary or motor part forrotating the cable drum and a control member for regulating the outputof the primary part over a controlling range from maximum win-ding-upover a neutral setting to maximum unwinding, the improvement comprisingautomatic control means for maintaining a constant tension in a winchcable wound on the cable drum when winding-up or unwinding under load,said means comprising a housing structure defining first and secondadjacent parallel cylinder spaces, said first of said cylinder spacesbeing in fluid communication with the outlet Huid pressure of theprimary part, first an-d second interconnected pistons reciprocable insaid iirst and second cylinder spaces, respectively, and operativelyconnected to the control member for correlated movement, spring meansacting on said pistons urging the control member toward the maximumwind-up position, adjustable means adapted to pre-determine the forceproduced by said spring, a passage disposed in said housingcommunicating said rst cylinder space with said second cylinder space atthe position of said iirst piston corresponding to the neutral setting4of the control member and said second cylinder space having means ofcommunication for discharge of the fluid pressure within said secon-dcylinder space only during movement of said pistons corresponding to thewinding-up range of the control member.

2. Control means for "a hydraulic winch as in claim 1 wherein said firstand second pistons have substantially equal effective fluid pressuresurface areas and disengaging -means are interposed in the operativeconnection between said pistons and the control member selectivelyrendering the operative connection between said pistons and the controlmember ineiective to facilitate manual operation of the control member.

References 4Cited the file `of Athis p etent rUNITED s-*TATES PATENTSHermlzirl et :aL 2 July 16, 19:46 cPattetsoii 2 L May 22, 19x51Gratzrrirller A.. Ian. 24, 195.6

